Improved mode of making cast-steel dasting-s



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Letters Patent No. 90,925, dated June 8, 1869.

IM1 ROV'ED MO DE OI MAKING CAST-STEEL CASTING-S.

The: Schedule-referred to in these Letters Patent and making pant of the same.

Be it known that I, THOMAS J. OHUBB, of Williamsburg, Kings county, State of New York, have discovered and invented new Improvements in Making Gast- Steel Castings, and mode of. casting the same; and I do hereby declare that the following is a full, clear, and exact description thereof.

The nature of my invention consists in a peculiar mode of heating to a higherdegree of heat than is usual previous to pouring it into the moulds by means of the ignition of highly -heated or superheated gas and heated air, whereby the molten steel is made more "fluidgvandwiii therefore Howthrough all parts of the mouldfmaking cast-steel castings of any desired size and. shape, and in the peculiar mode of reducing or' making the steel in a stationary fixed vessel in an arched-top furnace, where the combustion ofthe heated gas and heated air. takes place directly beneath the side arch, and in neag contact witlrthe metal, and by the process of reducing the quantity of carbon in the molten metal after the refining, and just previous to tapping, discharging, or casting the steel.

The heat may be brought up to such a high degree, without burning or injuring the metal, that the object maybe effected by causing the steel to flow to -all parts of the mould.

The application of my gas-producer, gas and airheating apparatus, and stationary melting and refining vessel to this purpose, enables me to make and refine the crude metal into steel, and by the peculiar management of the heat, the gas, and the air, I can deliver it from the furnace into the moulds at a much higher heat, and consequently more fluid, with the same amount of carbon in the metal or steel, as is usual.

To enable others skilled in the art to use my. improvement, I will proceed to describe the process and mode of operation.

I construct a furnace of any of the usual forms of arched-top furnaces, and place therein a stationary fixed vessel, or arrange a chamber or chambers in the furnace for receiving and retaining the' metal during the process of melting, refining, and reducing. I attach thereto an apparatus for heating or reheating gas and heating air, and arrange a gas-producer, or

fines leading therefrom into the gas-heating 0r intensifying chamber.

I preferably use a furnace similar to one described ina specification annexed to a separateapplication filed herewith, or a furnace such as is described in my patent of 1867 and 1868, or similar class of furnaces.

I am enabled by these means, or by the application of hi ghly-heated air and reheated gas separately introduced into the refining-chamber, to produce an intense heat directly in contact, or near the metal, and by regulating the peculiar character or quantity of the gas or air, I burn outer liquefy the foreign matter, without materially reducing the quantity of carbon in contact with the metal until it is refined, and then I bring up the heat by introducing a surplus of highly-heated air, which attacks the carbon or surplus carbon in the metal, decreasing the quantity, and that same operation increases the heat, as described.

By this process there is a large quantity of carbon and consequently fluidity retained in the metal during the time of extracting the foreign matter.

The metal becomes less burned, and the heat is raised in the end of the refining-process, so as to deliver the metal or steel into the moulds 'in a more fluid state than in the old way, by which means it flows to all parts of the moulds.

For large castings, or for castings having many long narrow passages in the moulds for the metal to flow through, I prefer using dry sand or dry-clay moulds, and sometimes I prefer the moulds heated.

I claim- 1. Producing cast-steel castings by means of or aid of highly-heated gas or gases, and heated air, as herein described.

2. Theprocess of converting or making cast steel herein described, with the process of making cast-steel castings.

The application and combination of a gas-producer and an air-heating and gas-heating apparatus or furnace, and a stationary melting and refining-vets sel or chamber for melting and refining metal for making cast-steel castings.

Witnesses:

JACOB RnPPEn'r, JOHN STEWART.

THOS. J. GHUBBI 

